Extension-bit or drilling-tool.



PATBNTED Nov. 24, 190s.

l I D. L. LUDDINGTON. EXTENSION BIT 0R DRILLING TOOL.

APPLIOATION FILED AUG, 3. 1903.

H0 IODEL.

WJTNESSES KNEW ZTa-w.

v UNITED STATES Patented November 24, 11903.

PATENT EEICE.

DANIEL LOUIS LUDDINGTON, OF GRASS VALLEY, CALIFORNIA, ASSIGNOR OE ONELHALF TO GEORGE MAINIIART, OE GRASS VALLEY, CALIFORNIA.

EXTENSlON-IT @R ORlLLlNG==TOL SPECIFICATION forming part of Letters iatent ...To. 744,925, dated November 24, 1903. Application filed August 3, 1903.k Serial No. 168,029. (No model.)

To @ZZ whom it may concern:

Be it known that LDANTEL LoUls LUDDINGV- TON, a citizen of the United States, residing at Grass Valley, in the county of Nevada and '5 State of California, have invented new and useful Improvements in Extension-Bits or Drilling-Tools, of -which the following is a specification.

Thisinvention has relation to improve- Io ments in drilling-tools; and it consists in the novel construction,combination,and arrangement of parts of which it is composed, whereby the bit is extensible while the process of drilling is carried out, all as will be herein- I after more fully explained, and particularly pointed out in the appended claim.

The annexed drawings, to which reference is made, fully illustrate my invention, in which 2o Figure l represents a side View of my improved drilling-tool. Fig. 2 is a vertical longitudinal sectional view of the same, and Fig. 3 represents a transverse vertical sectional view.

Referring by letter to the accompanying drawings, A designates the hand drilling-tool, comprising the body portion or handle ct, which is provided with a central opening Z) to receive the stem c of the bit-holder d, which 3o latter is hollow, providing` a central passage e for the bit, and the same is constructed with an enlarged portionf, having a shoulder g, adjacent to which is a pinion h, arranged upon the narrow stem of the holder. Se-

cured to the handle is a spring-arm t', provided with a notch or cut-away portion j opposite to the pinion, and the end thereof has an openingzt, in which is seated akey or wearpin l, that is designed to hold the pinion in 4o place. This spring-arm will yield when the notched end thereof is raised to permit the pinion 7L to pass the inner end of the pin Z in detaching the bit-holder CZ from the body or handle d or attaching the same to said handle. The bit after insertion into the hollow holder and adjusted in position is held in place by a set-screw m on the holder.

B represents a bar, which is provided with teeth n, that engage the teeth of the pinion,

and the same is provided with a handle o, by 5o which said toothed bar is operated.

Having thus described the various parts of which my device is composed, I will now explain its operation. The bit being adjusted within the hollow holder and the toothed bar arranged within the eut-away portion and engagingthe pinion, the operatorgrasps the handle of the toothed bar and draws and forces the same back and forth, which causes the pinion to revolve first in one direction and then an* 6o other direction, thereby reversing the revolution of said pinion with every stroke of the toothed bar, thus imparting such movement to the bit in drilling. A string or wire 19 is connected to the inner end of the bit and serves to bring the bit forward in adjusting the same, and the notch or cutaway portion in the end of the spring-arm serves as a guide to the toothed bar in its movements.

It will be seen that the wear-pin l being de- 7o taehable the same can be withdrawn when worn and replaced by another.

I do'not wish to be confined to the exact construction of my device, as various changes may be made in its construction without departing from the spirit of my invention.

INhat I claim as new, and desire to secure by Letters Patent, is-

The combination with the bit, hollow holder and handle, said holder provided with the 8o pinion, of the toothed bar and spring-arm, the latter provided with the notch adjacent to said pinion, and the pin inserted in the end of said arm and adapted to hold the pinion in position, as shown and described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

DANIEL LOUIS LUDDINGTON.

Witnesses:

Gno. MAINHAET, GEO. E. MAINHAET. 

